1, the barcode on the product is printed during production. But some valuable goods in the mall will be labeled with anti-theft bar codes.

As the last question, the bar code is not attached to every product. For supermarket management, bar codes will be attached to milk powder, tea, cosmetics and so on. If you pay attention, there are generally two bar codes on the goods, and the one attached is the anti-theft bar code.

4. The anti-theft bar code is magnetized by the coil, and the coil is stuck on the back of the bar code.

Your analysis is correct, but now that RFID technology has been used in supermarkets, it is not so easy to take it out.

Extended data:

The empowerment of the manufacturer code is organized by the article codes of various countries or regions, and China is given the manufacturer code by the National Article Coding Center. Commodity code is a code used to identify commodities, and the distribution right of the code is exercised by the product manufacturing enterprises themselves. At last, the 1 parity code is used to check the correctness of the L- 12 digital code from the left in the barcode.

Commodity barcode refers to a symbol composed of a group of regularly arranged bars, spaces and their corresponding characters, which is used to represent certain commodity information. Among them, the bar is dark and empty, which is a reading device used to scan and read bar codes.

Its corresponding characters consist of a group of Arabic numerals for people to read directly or input data to the computer through the keyboard. This set of spaces and corresponding characters represent the same information.

Bar code technology was born with the development and application of computer and information technology. It is a new technology integrating coding, printing, identification, data acquisition and processing. The use of bar code scanning is the general trend of market circulation in the future, and it must follow the relevant provisions of commodity bar code management.

At present, the commonly used coding systems in the world are EAN barcode, UPC barcode, 25 barcode, cross barcode, Kudba barcode, Sanjiu barcode and 128 barcode, and the most commonly used commodity is EAN commodity barcode.

EAN commodity bar code, also known as general commodity bar code, is formulated by ean international and is widely used in the world. It is the most widely used commodity bar code in the world. This kind of barcode is also widely used in China. EAN commodity bar codes are divided into EAN- 13 (standard version) and EAN-8 (abbreviated version).

The coding of commodity bar codes follows the principle of uniqueness, so as to ensure that commodity bar codes will not be repeated in the global scope, that is, a commodity item can only have one code, or a code can only identify one commodity item. Commodities with different specifications, different packages, different varieties, different prices and different colors can only use different commodity codes.

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